James has been a stalwart of United’s squad since the club was formed ahead of the 2018-19 season. She scored their first goals in the Championship and the Women’s Super League and was the first woman to score at Old Trafford.
The 19-year-old has been linked with a move away from Manchester for several months, with a return to London the top target.
The Guardian have reported that her transfer is record-breaking for involving the most money ever exchanged between two WSL clubs.
She played with both Chelsea and Arsenal at youth level and made her senior debut for the latter when she was just 15.
The striker then moved down to the Championship with newly formed United and scored 14 goals in her first season, helping the side to WSL promotion at the first time of asking.
Injury hampered parts of her 2020-21 season but she leaves the club as their second all-time top scorer with 28 goals. Ella Toone leads the way with 32.
James is the latest in a number of high profile names to leave the club with USWNT World Cup winners Christen Press and Tobin Heath both returning to the National Women’s Soccer League and manager Casey Stoney resigning.
The Athletic have reported that there has been anger amongst the squad over the facilities and care given by the club to the women’s side which is still without a manager after Stoney’s departure.